Radial astrocytes, also known as radial glia, are a specialized type of astrocyte that play important roles in the development and maintenance of the central nervous system. During embryonic development, radial astrocytes serve as scaffolding for the migration of neurons from the ventricular zone to their final positions in the brain. Once neurons have reached their final destinations, radial astrocytes can differentiate into mature astrocytes or persist in the adult brain as a specialized subtype of astrocyte.

They have a characteristic elongated morphology, with processes that extend from the ventricular surface to the pial surface of the brain. These processes serve as guides for migrating neurons, providing a physical substrate for migration and directing the growth of axons and dendrites. They also secrete factors that promote neuronal migration and differentiation, and they can modulate the chemical environment of the developing brain through the uptake and release of neurotransmitters and other signaling molecules.

In the adult brain, radial astrocytes can play important roles in neural plasticity and repair. Under certain conditions, such as after injury or in response to neurodegenerative diseases, radial astrocytes can become reactive and adopt a morphology similar to that of radial glia during development. This reactive gliosis can have both beneficial and detrimental effects on the brain, depending on the context and severity of the insult.

Overall, they are a specialized subtype of astrocyte that play critical roles in brain development and function, and their dysfunction has been implicated in a variety of neurological disorders.